These data are part of a larger USGS project to develop an updated geospatial database of mines, mineral deposits and mineral regions in the United States. Mine and prospect-related symbols, such as those used to represent prospect pits, mines, adits, dumps, tailings, etc., hereafter referred to as “mine” symbols or features, are currently being digitized on a state-by-state basis from the 7.5-minute (1:24, 000-scale) and the 15-minute (1:48, 000 and 1:62,500-scale) archive of the USGS Historical Topographic Maps Collection, or acquired from available databases (California and Nevada, 1:24,000-scale only). Compilation of these features is the first phase in capturing accurate locations and general information about features related to mineral resource exploration and extraction across the U.S. To date, the compilation of 400,000-plus point and polygon mine symbols from approximately 51,000 maps of 17 western states (AZ, CA, CO, ID, KS, MT, ND, NE, NM, NV, OK, OR, SD, UT, WA, WY and western TX) has been completed. The process renders not only a more complete picture of exploration and mining in the western U.S., but an approximate time line of when these activities occurred. The data may be used for land use planning, assessing abandoned mine lands and mine-related environmental impacts, assessing the value of mineral resources from Federal, State and private lands, and mapping mineralized areas and systems for input into the land management process. The data are presented as three groups of layers based on the scale of the source maps. No reconciliation between the data groups was done.

Version 10.0 of these data are part of a larger U.S. Geological Survey (USGS) project to develop an updated geospatial database of mines, mineral deposits, and mineral regions in the United States. Mine and prospect-related symbols, such as those used to represent prospect pits, mines, adits, dumps, tailings, etc., hereafter referred to as “mine” symbols or features, have been digitized from the 7.5-minute (1:24,000, 1:25,000-scale; and 1:10,000, 1:20,000 and 1:30,000-scale in Puerto Rico only) and the 15-minute (1:48,000 and 1:62,500-scale; 1:63,360-scale in Alaska only) archive of the USGS Historical Topographic Map Collection (HTMC), or acquired from available databases (California and Nevada, 1:24,000-scale only). Compilation of these features is the first phase in capturing accurate locations and general information about features related to mineral resource exploration and extraction across the U.S. The compilation of 725,690 point and polygon mine symbols from approximately 106,350 maps across 50 states, the Commonwealth of Puerto Rico (PR) and the District of Columbia (DC) has been completed: Alabama (AL), Alaska (AK), Arizona (AZ), Arkansas (AR), California (CA), Colorado (CO), Connecticut (CT), Delaware (DE), Florida (FL), Georgia (GA), Hawaii (HI), Idaho (ID), Illinois (IL), Indiana (IN), Iowa (IA), Kansas (KS), Kentucky (KY), Louisiana (LA), Maine (ME), Maryland (MD), Massachusetts (MA), Michigan (MI), Minnesota (MN), Mississippi (MS), Missouri (MO), Montana (MT), Nebraska (NE), Nevada (NV), New Hampshire (NH), New Jersey (NJ), New Mexico (NM), New York (NY), North Carolina (NC), North Dakota (ND), Ohio (OH), Oklahoma (OK), Oregon (OR), Pennsylvania (PA), Rhode Island (RI), South Carolina (SC), South Dakota (SD), Tennessee (TN), Texas (TX), Utah (UT), Vermont (VT), Virginia (VA), Washington (WA), West Virginia (WV), Wisconsin (WI), and Wyoming (WY). The process renders not only a more complete picture of exploration and mining in the U.S., but an approximate timeline of when these activities occurred. These data may be used for land use planning, assessing abandoned mine lands and mine-related environmental impacts, assessing the value of mineral resources from Federal, State and private lands, and mapping mineralized areas and systems for input into the land management process. These data are presented as three groups of layers based on the scale of the source maps. No reconciliation between the data groups was done.

This U.S. Geological Survey (USGS) data release contains data from stream water, groundwater/springs, and sediment samples collected from legacy mine land (LML) sites in central Colorado. The sites were selected using a GIS-based approach that integrated regional geological and geochemical datasets with known mine features and satellite data identifying hydrothermal alteration (ASTER) to identify LML-impacted watersheds with low natural background or metal concentrations slightly above aquatic life standards. The central Colorado watersheds selected for preliminary investigation included 1) McNasser Gulch, 2) upper South Fork Lake Creek, 3) Saints John Creek, and 4) Hall Valley (north fork of South Platte River). Reconnaissance sampling of surface water, groundwater, and sediment (August 2019) to identify sources of trace element contamination in each watershed. Follow-up sampling in the Hall Valley watershed (August 2020) provided flow and concentration data for the four largest surface inflows to a headwater pond and additional locations below the pond outlet. Metal loads at these locations were calculated as the product of flow and concentration.

The polygon (vector) feature class represents locatable mineral resource assessment tracts (tracts of land) associated with the Department of the Interior (DOI) Sagebrush Focal Areas (SFAs) in Montana, Wyoming and Utah, central Idaho, and the Oregon-Nevada-Idaho border area. The mineral-resources tracts are geographic areas that were assessed by the USGS and were determined to be geologically favorable for a deposit type of interest to a depth of 1 kilometer. Qualitative assessment methods outlined by the Bureau of Land Management (BLM) were used to develop tract boundaries and to assign a level of mineral-resource potential and certainty to each tract. The general process included (1) identifying possible mineral deposit types for locatable commodities specified by BLM for each focal area, (2) outlining those areas that potentially contained mineral deposits based on geology, mineral occurrences, geophysics, soil and stream-sediment geochemistry, alteration mineral assemblages inferred from satellite imagery, BLM claims and permit data, mineral-exploration activity, and existing mineral-resource assessment data, and (3) evaluating the level of mineral-resource potential and level of certainty associated with the outlined areas using BLM assessment categories. A full description of the assessment is provided in the accompanying report (Day and others, 2016). SFAs, identified by agencies of the DOI, are high-quality sagebrush habitat areas supporting high densities of breeding greater sage-grouse (Centrocercus urophasianus). SFAs are within priority habitat areas or areas where land-use measures are intended to minimize or avoid habitat disturbance. Seven SFAs are within the USGS Sagebrush Mineral-Resource Assessment Project study area. They include the Bear River Watershed, North-Central Idaho, North-Central Montana, Southeastern Oregon and North-Central Nevada, Sheldon-Hart Mountain National Wildlife Refuge Complex, Southern Idaho and Northern Nevada, and Southwestern and South-Central Wyoming SFAs, as well as additional areas in Nevada (termed the “Nevada additions”) proposed by the State of Nevada. Landscape-scale conservation efforts by the BLM, U.S. Fish and Wildlife Service (FWS), the U.S. Forest Service (USFS), State agencies, private land owners, and other partners are striving to conserve the breeding sagebrush habitat for the greater sage-grouse across these areas. Accompanying report (Chapter A): Day, W.C., Hammarstrom, J.M., Zientek, M.L., and Frost, T.P., eds., 2016, Overview with methods and procedures of the U.S. Geological Survey mineral-resource assessment of the Sagebrush Focal Areas of Idaho, Montana, Nevada, Oregon, Utah, and Wyoming: U.S. Geological Survey Scientific Investigations Report 2016–5089, 211 p., http://dx.doi.org/10.3133/sir20165089.

The polygon (vector) feature class represents locatable mineral resource assessment tracts (tracts of land) associated with the Department of the Interior (DOI) Sagebrush Focal Areas (SFAs) in Montana, Wyoming and Utah, central Idaho, and the Oregon-Nevada-Idaho border area. The mineral-resources tracts are geographic areas that were assessed by the USGS and were determined to be geologically favorable for a deposit type of interest to a depth of 1 kilometer. Qualitative assessment methods outlined by the Bureau of Land Management (BLM) were used to develop tract boundaries and to assign a level of mineral-resource potential and certainty to each tract. The general process included (1) identifying possible mineral deposit types for locatable commodities specified by BLM for each focal area, (2) outlining those areas that potentially contained mineral deposits based on geology, mineral occurrences, geophysics, soil and stream-sediment geochemistry, alteration mineral assemblages inferred from satellite imagery, BLM claims and permit data, mineral-exploration activity, and existing mineral-resource assessment data, and (3) evaluating the level of mineral-resource potential and level of certainty associated with the outlined areas using BLM assessment categories. A full description of the assessment is provided in the accompanying report (Day and others, 2016). SFAs, identified by agencies of the DOI, are high-quality sagebrush habitat areas supporting high densities of breeding greater sage-grouse (Centrocercus urophasianus). SFAs are within priority habitat areas or areas where land-use measures are intended to minimize or avoid habitat disturbance. Seven SFAs are within the USGS Sagebrush Mineral-Resource Assessment Project study area. They include the Bear River Watershed, North-Central Idaho, North-Central Montana, Southeastern Oregon and North-Central Nevada, Sheldon-Hart Mountain National Wildlife Refuge Complex, Southern Idaho and Northern Nevada, and Southwestern and South-Central Wyoming SFAs, as well as additional areas in Nevada (termed the “Nevada additions”) proposed by the State of Nevada. Landscape-scale conservation efforts by the BLM, U.S. Fish and Wildlife Service (FWS), the U.S. Forest Service (USFS), State agencies, private land owners, and other partners are striving to conserve the breeding sagebrush habitat for the greater sage-grouse across these areas. Accompanying report (Chapter A): Day, W.C., Hammarstrom, J.M., Zientek, M.L., and Frost, T.P., eds., 2016, Overview with methods and procedures of the U.S. Geological Survey mineral-resource assessment of the Sagebrush Focal Areas of Idaho, Montana, Nevada, Oregon, Utah, and Wyoming: U.S. Geological Survey Scientific Investigations Report 2016–5089, 211 p., http://dx.doi.org/10.3133/sir20165089.

Sediment hosted gold deposits in Nevada were first mined in the 1960s from open pit mines with large tonnage and low grade resources. Since that time, continuing exploration and discovery have identified extraordinary resources, and together these deposits now form the second-largest gold endowment on Earth, surpassed only by the Witwatersrand Gold Fields of South Africa. The data herein are part of a larger U.S. Geological Survey (USGS) project to develop an updated geospatial database of mines, mineral deposits and mineral regions in the United States. The point and polygon layers within this database represent locations of mines, mineral occurrences (which includes deposits and prospects), and mining districts in an approximately 200-square mile area northwest of Carlin, Nevada. Tables contain additional information such as commodity, geology, deposit types, activity status, deposit resources, and mine production. The extent of surface workings, when visible on imagery, is also captured and shows the relative size of mining operations. All data were compiled from publicly available sources published from 1910 - 2017. Where possible, data were compiled from primary source reports rather than from syntheses of past reports. Although the selected area does not include the entire Carlin Trend, the area, which covers nine 7.5-minute quadrangles, does contain a wide range of deposit types described through a variety of public data and information. These data are being compiled by the USGS Mineral Deposit Database project with support from the Bureau of Land Management.

Sediment hosted gold deposits in Nevada were first mined in the 1960s from open pit mines with large tonnage and low grade resources. Since that time, continuing exploration and discovery have identified extraordinary resources, and together these deposits now form the second-largest gold endowment on Earth, surpassed only by the Witwatersrand Gold Fields of South Africa. The data herein are part of a larger U.S. Geological Survey (USGS) project to develop an updated geospatial database of mines, mineral deposits and mineral regions in the United States. The point and polygon layers within this database represent locations of mines, mineral occurrences (which includes deposits and prospects), and mining districts in an approximately 200-square mile area northwest of Carlin, Nevada. Tables contain additional information such as commodity, geology, deposit types, activity status, deposit resources, and mine production. The extent of surface workings, when visible on imagery, is also captured and shows the relative size of mining operations. All data were compiled from publicly available sources published from 1910 - 2017. Where possible, data were compiled from primary source reports rather than from syntheses of past reports. Although the selected area does not include the entire Carlin Trend, the area, which covers nine 7.5-minute quadrangles, does contain a wide range of deposit types described through a variety of public data and information. These data are being compiled by the USGS Mineral Deposit Database project with support from the Bureau of Land Management.